Georgia Tech brings back eight starters on defense, but defensive coordinator Ted Roof has concerns about replacing the three he lost — linebacker P.J. Davis, defensive tackle Patrick Gamble and defensive end Rod Rook-Chungong.

“Because that was a very, maybe underrated, under-noticed part of our defense last year with the leadership of Pat and P.J. and Rook and (linebacker) Chase Alford,” Roof said. “All those guys, that does leave a vacuum and it’s up to the guys coming back to be able to do that.”

With eight starters back, there’s plenty of candidates for players who can carry the banner with the passion and toughness that Davis, Gamble and Rook-Chungong exemplified. Linebacker Brant Mitchell, defensive KeShun Freeman and safety Corey Griffin are but three. The four other returning starters in the secondary — Lance and Lawrence Austin, Step Durham and A.J. Gray — are four more.

“There’s some guys that have played a lot of football,” Roof said. “A lot of guys are trying to step up, but it’s got to be a consistent step up. It can’t be seven days we’re up and we’re rolling and one day we’re not. There’s got to be some consistency with the leadership and that’s something we’re trying to develop.”

Safeties coach Andy McCollum said he is looking for a lead-by-example type.

“It’s easy to be a rah-rah guy when things are going good,” he said. “P.J. was a guy that, when things were going down — Pat Gamble was the same way — they’re guys that, when things are going tough, they’re going to rise up their play.”

Gamble, a captain, and other team members asserted their leadership towards the end of the season after the Jackets gave up 636 yards in a 48-20 loss at North Carolina on Nov. 5. The yaradge total was the second highest allowed in school history. Gamble sought more from himself and his teammates, and the defense’s play picked up in the final four games, all wins for the Jackets.

" That's something that I'll always remember those guys for ," Roof said earlier in the spring.

Mitchell acknowledged the void left by Davis.

“It’s hard,” he said. “It takes the whole team. It takes everybody coming together and playing as one. It’s not 11 on 1, it takes all 11 guys. I think that’s a big thing with us. I think we have really good chemistry and I think that started last year in the offseason. We tried to get close as a team and stuff, and I think if we come together, we can fill all the spots that need to be filled.”